Automatic loading and unloading apparatus for washers, sterilizers and like vessels

ABSTRACT

The invention concerns a washer, sterilizer or like vessel and apparatus for automatically loading and unloading articles from the vessel. The apparatus includes a conveyor for bringing articles to the vessel, a transfer mechanism for moving the articles between the conveyor and vessel opening and a boom arranged to move the articles into or out of the vessel.

o I; Unite States Patent 1 [111 3,73,5@

Lawson June 12, 1973 [54] AUTOMATIC LOADING AND UNLOADING 2,965,36912/1960 Acker et al. 198/221 X APPARATUS FOR WASHERS, STERILIZERS fi a n3 on agmo AND LIKE VESSELS 2,668,614 2/1954 Lawson 198/221 [75]Inventor: Alfred C. Lawson, Fairport, N.Y. 3,300,195 H1967 Dovovan 6t[73] Assignee: Sybron Corporation, Rochester,

Primary Examiner--Robert G. Sheridan [22] F1 d A 14 1971AttorneyTheodore B. Roessel 1 e pr.

[21] Appl. No.: 133,897 ABSTRACT [52] U S Cl 214/23 198/106 198/221 Theinvention concerns a washer, sterilizer or like ves- [5 1] 25/10 se] andapparatus for automatically loading and unload- [58] Fieild 25 17 ingarticles from the vessel. The apparatus includes a 6 conveyor forbringing articles to the vessel, a transfer mechanism for moving thearticles between the con- [56] References Cited veyor and vessel openingand a boom arranged to move UNITED STATES PATENTS the articles into orout of the vessel.

3,104,767 9/1963 Bassett 214/23 2 Claims, 3 Drawing Figures PAIENIEU 2SNEEY20F3 N GE INVENTOR. ALFRED C LAWSON ATTORNEY PAIENTED 2W3 SHEET-3W3ATTOHNFY AUTOMATIC LOADING AND UNLOADING APPARATUS FOR WASHERS,STERILIZERS AND LIKE VESSELS BACKGROUND OF THE INVENTION The presentinvention relates to loading and unloading apparatus for washers,sterilizers and the like and more particular to apparatus forautomatically loading and unloading such vessels wherein the apparatusis stationed wholly outside the vessel.

Modern hospitals, pharmaceutical houses, laboratories or the likerequire an automated system for washing and sterilizing the largernumber of utensils, containers, equipment, etc. that is used during thecourse of its daily operation. Most efficient automatic operation ofwashers and sterilizers are accomplished by what is known aspass-through devices wherein the articles enter one end and exist theother. Loading mechanism in such types of washers are relatively simplein that an endless belt conveyor may be used to carry the articlethrough the washing vessel. Pass-through sterilizers, however, presentadditional problems especially where steam and/or high temperature isused as the sterilizing medium. In such cases the sterilizing vesselmust be sealed and accordingly loading apparatus such as an endless beltconveyor which passes through the vessel cannot be used. Attempt hasbeen made to overcome this problem by having a separate conveyor or loadreceiving means within the vessel which receives the articles from anexternal conveyor and then delivers the articles to another externalconveyor after the sterilizing process. However, this requires amechanism within the sterilizing vessel which not only must be able towithstand the humid and high temperature environment of a steam and/orhigh temperature sterilizer but which must also have its moving partsreadily accessible for cleaning, repair and/or replacement. Care mustalso be taken in the selection of materials from which such devices aremade to insure that the material does not adversely react with theenvironment within the sterilizing vessel as in the case where thesterilizing media is a toxic gas.

Accordingly, the present invention overcomes the drawbacks of the priorart by providing both loading and unloading apparatus which is locatedcompletely outside of the vessel and extends into the vessel only duringthe loading or unloading process so that the apparatus is not exposed tothe high temperature, humid or toxic environment within the washersterilizer vessel.

SUMMARY OF THE PRESENT INVENTION The present invention may becharacterized in one aspect thereof by the provision in combination witha pass-through washer and/or sterilizing vessel and a conveyor formoving the articles to and from the vessel, of a loading apparatuscomprising: a transfer means for transferring the articles from a loadconveyor and along a guide and support track into an opening of avessel; and a load means for moving the articles from the track into thevessel including a traversing boom adapted for pushing the articlesthrough the opening and into the vessel.

The unloading apparatus is similar in construction to the load apparatusbut is located on the unload side of the pass-through vessel wherein aboom member first is extended into the vessel for withdrawing thearticles onto a guide track and thereafter a transfer means moves thearticles along the guide track and onto a conveyor.

OBJECTS OF THE INVENTION One object of the present invention is toprovide loading and unloading apparatus for pass-through washers,sterilizers and like vessels which is located outside of the vessel andhas no moving parts contained within the vessel during the washingand/or sterilizing cycles.

Another object of this invention is to provide loading apparatus forpassthrough washers, sterilizers and like vessels having means forremoving articles to be washed and sterilized from a conveyor andtransferring such articles into the vessel.

A further object of the present invention is to provide a loader of thetype described wherein the articles to be washed and sterilized arefirst removed from a conveyor system to an intermediate transfermechanism and thereafter moved into the vessel.

Yet another object of the present invention is to provide a completelyautomated system for loading and unloading washers, sterilizers and likevessels.

These and other objects, advantages and characteriz' ing features of thepresent invention will become more apparent on consideration of thefollowing detailed description thereof when taken in connection with theaccompanying drawings depicting the same.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of anautomated washer sterilizer system employing the present invention;

FIG. 2 is a side elevation view partly broken away and in section of theloading apparatus of the present invention; and

FIG. 3 is a front elevation view of the apparatus shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the Drawings, FIG.1 shows schematically a general plan view of an automated systememploying the present invention. The system uses three vessels 10, 12and 14 which may be either washers or sterilizers or of the type whereinboth washing and sterilizing is carried out in the same vessel. Whilethe Figure shows three such vessels, it should be appreciated that agreater or lesser number of vessels may be used as necessary dependingupon the requirements of the particular hospital, pharmaceutical house,laboratory or the like.

A conveyor 16 may be used to route the articles from a source (notshown) to that room 17 or part of the building containing thewasher-sterilizer apparatus. Any suitable conveyor mechanism may be usedalthough a driven roller accumulating conveyor is preferred. The sourceof the articles, for example, could be a collecting and sorting roomwhere the various articles to be washed and sterilized are sorted andpacked in containers 18 which are then loaded on to the conveyor.

From conveyor 16 or other suitable transport device, containers 18 areshuttled onto a shuttle conveyor 20 which extends into room 17. Means 19for transferring and controlling the movement of the containers fromconveyor 16 to shuttle container 20 are well known in the conveyor artand form no part of the present invention. For example, such means couldbe a photo cell operated mechanism which is triggered by passingcontainers to move containers from conveyor 16 to the shuttle conveyor.

Shuttle conveyor 20 is preferably a roller conveyor for purposesdescribed hereinbelow which may be either gravity operated or of thepowered roller type. The shuttle conveyor is disposed for moving thecontainers 18 along a path of travel which is normal to the path throughthe pass-through vessels and spaced from the load openings of thevessels.

The loading apparatus of the present invention, generally indicated at22, is located in the space between each vessel and the shuttleconveyor, with a portion of the loader extending beneath the shuttle.The loader moves containers, which have been accumulated (in a mannerset forth hereinbelow) on the shuttle conveyor in front of the vessels,from this accumulate position on the conveyor across the space betweenthe conveyor and the vessel, and into the vessel.

As shown in FIG. 2, loader 22 includes a stand 42 which supports a pairof spaced, parallel rail members 44 at the level of the vessel opening43 and more particularly at the level of any suitable article receivingmeans 32 within the vessel. These rails 44 support and guide containers20 as the containers are moved across the loader and into the vessel.

FIG. 3 shows that stand 42 carries two sets of such rails so that twocontainers may be moved side by side into the washer and/or sterilizervessel. In like respect, other portions of the loader are alsoduplicated as will be readily apparent from the view shown in FIG. 3. Tosimplify the description, however, duplicate parts performing identicalfunctions have been given the same reference numeral but otherwise, thedevice and its operation will be described in the singular as if thisside by sidesymmetry did not exist.

Stand 42 also supports the drive motors 46,48 which drive the loadtransfer mechanism as set out hereinbelow. Drive motor 46 operatingthrough any suitable drive means such as a chain and sprocket indicatedat 50 (FIG. 2) drives a shaft 52 which extends substantially the fullwidth of the loader (FIG. 3.) Keyed to this shaft are a pair ofsprockets 54 which are located inboard of the spaced rail members 44. Asviewed in FIG. 2, each sprocket 54 drives a transfer chain 56 which runsin a clockwise direction in a closed loop extending from sprockets 54,over idlers 58, 60 and 62 back to the sprockets. Thus, one terminus ofthe closed loop is represented by sprockets 54. Idlers 60 and 62 arespaced outwardly from stand 42 to carry the transfer chain beneathshuttle conveyor 20 and between adjacent rollers of the shuttleconveyor. In addition, each transfer chain runs along a horizontal guidechannel 64, best shown in FIG. 3 located just below the level of rails44 which prevents the chain from sagging as it moves past the rails.

Attached to each transfer chain 56, preferably at l80 intervals, arepusher dogs '66 which extend above the level of rails 44 .as thetransfer chains move along the guide channels. With this arrangement,these pusher dogs will engage the bottom of a container on the shuttleconveyor when the transfer chain is driven to move the container fromthe conveyor, onto the rails 44 and along these rails into the opening43 of the vessel.

Second drive motor 48 is reversable and operating through any suitablemeans such as chain and sprocket drive generally indicated at 68 (FIG.3), drives a sprocket wheel 70. Sprocket wheel 70 in turn drives a leadscrew 72 which isjournaled adjacent the front and rear of frame 42 asbest seen in FIG. 2. Above and below the lead screw and extendingparallel with the axis of the lead screw is, respectively, a lower guiderod 74 and an upper guide rod 76. These guide rods slidably support anupright traveling member or slave nut 78 which is driven horizontally bylead screw 72. The traveling member supports at its upper end 80, a boom82 in cantilever fashion. Journaled to the forward end 84 of the boom isa pusher element 86 which is normally biased to an upright position, asshown, extending above the plane of rails 44 so that the pusher elementmay engage against a container riding on the rails. While pusher 86 isbiased to this upright position by a spring 88, the pusher element maybe rotated in a clockwise direction as viewed in FIG. 2 about its axis90 whenever a container engages the rear surface 92 of the pusher forpurposes set out hereinbelow.

In operation, means 19 operates to transfer containers 18 from conveyor16 onto shuttle conveyor 20. When two containers have accumulated infront of vessel 10 as shown in FIG. 1, a stop 24 is raised to preventthe passage of additional containers until these first two have beenloaded into vessel 10. This stop 24 forms no part of the presentinvention and means for preventing movement of articles on a rollerconveyor are well known in the art. When the first two containers havebeen transferred by loading apparatus 22 from the shuttle conveyor andinto vessel 10, stop 24 is dropped to permit the accumulation of twomore containers in front of vessel 10 and the stop 24 again raised. Thiscontinues until such time as vessel 10 is fully loaded and beginsoperation. At this point, stop 24 is raised to permit the accumulationof two containers in front of vessel 12 as shown in dotted line inFIG. 1. When this occurs, a stop 26 is raised to prevent furtheraccumulation of containers in front of vessel 12 until the containerswhich have been so accumulated have been transferred by the loadingapparatus into vessel 12. Stop 26 is then lowered to permit two morecontainers to accumulate in front of vessel 12 and the raising andlowering of stops continues until all the vessels are filled to capacityand are in operation. When this occurs, means 19 for transferringcontainers from conveyor 16 onto shuttle conveyor 20 prevents suchtransfer until one or more of the vessels are empty and ready to receivecontainers.

The operation of the loading apparatus will be described as beginningwhen two containers 18 are occupying the accumulation positions on theshuttle conveyor 20 in front of vessel 10 as shown in FIG. 1. with thecontainers in this position, any suitable means such as a pair of limitswitches 30 closes a circuit to activate drive motor 46. Drive motor 46operating through chain and sprocket drive 50, moves transfer chains 56in a clockwise direction as viewed in FIG. 2 over sprockets 54, idlersprockets 58,60,62 and through guide channel 64. As the chain is movedin this clockwise direction, one of the dogs 66 is eventually engagedagainst the rear side of the container and the container moved by thisengagement from the roller conveyor onto and along rails 44. As thecontainer is moved along the rails, the rearward end 92 of pusher 86 isengaged by the container which rotates the pusher out of the containerpath of travel so that the container may pass over the pusher. The chain56 continues to carry container along rails 44 to a first positionwherein the container is passed off of the rails and partially into thevessel opening. Rack 32 in the vessel which is at the same height asrails 44 receives the containers as they move off of the rails and intothe vessel. At this point, dog 66 rotates around sprocket 54 anddisengages from the container.

As the container is moved along rails 44 by the chain and just prior toentering the vessel opening 43, the container actuates another limitswitch 34. Closing limit switch 34 actuates suitable control means suchas a stepping switch (not shown) which allows the container to proceedif the vessel door is open. As the container passes onto rack 32 withinthe vessel, it clears limit switch 34 which stops drive motor 46 andstarts drive motor 48. At this point, the container is only partly inthe vessel.

Motor 48 acting through chain and sprocket drive 68 and sprocket 70drives worm 72 to move the upright slave nut 78 and the cantileveredboom 82 to the right as viewed in FIG. 2. Pusher element engages therear of the container and pushes the container completely through thevessel opening further onto rack 32. When the pusher has reached itsforward limit of travel, it engages still a third limit switch 36 whichcauses drive motor 48 to reverse to return the pusher to the positionshown in FIG. 2. Any suitable means such as a limit switch (not shown)may be provided to stop motor 48 when the pusher has been returned tothe position shown in FIG. 2.

If, in the meantime, two additional containers 18 have been accumulatedin front of vessel 10 as shown in FIG. 1, the actuation of limitswitches 30 coupled with the return of the pusher will begin the loadingcycle again. Loading these additional containers into the vessel willsimply push the previously loaded containers further into the vessel.This loading procedure continues until the vessel is loaded and thevessel door closed.

As an alternative to this loading method, motor 48 can be started assoon as limit switch 34 is closed. With this arrangement there is, for ashort period of time, simultaneous movement of both the chain and thepusher. However, the pusher is purposely driven at a slower speed thanthe chain so that the pusher will not engage the container until the dogrotates around sprocket 54 and disengages from the container. Sincechain 56 preferably has only two dogs 66 located at 180 intervals, it isa simple matter to control or program drive motor 46 to stop when dog 66rotates around sprocket 54 and disengages from the container. At thispoint, pusher element 86 engages the rear of the container and pushesthe container to a second position completely through the vessel openingand onto rack 32. When the pusher has reached the forward limit oftravel, it engages limit switch 36 which causes drive motor 48 toreverse to return the pusher to the position shown in FIG. 2. As thepusher is being returned to the position shown in FIG. 2, drive motor 46may be actuated to move any containers which have accumulated in themeantime, off of the roller conveyor and across rails 44 into the vesselopening. Thus, by the time pusher has returned to its start position,two additional containers are in place readyto be moved through theopening and into the vessel. Should chain 56 be moving a container alongrails 44 as the boom 82 is being returned, the container will engage thepusher surface 92 to move the pusher out of the way against the bias ofspring 88 as the container and pusher move past other. If the vessel iscapable of receiving additional containers, the container now on rails44 will be moved into the vessel in the manner described hereinabove.The previously loaded containers will simply be pushed further into thevessel by the after loaded containers.

The unload apparatus, generally indicated at 38 (FIG. 1), which operatesat the end of the wash and/or sterilize cycle to remove containers fromthe vessel, is very similar in construction to the load devices asdescribed hereinabove.

Accordingly, the construction and operation of the unloading apparatuswill not be described in detail as modifying the loading apparatus 22 toproduce the unloading apparatus is within the skill of the art. It issufficient for purposes of the present invention merely to say thatwhile the loading and unloading apparatus are similar in construction,the unloading apparatus operates in the reverse of the loadingapparatus. In this respect, the pusher elements of the unloader arepulling elements, that is, they are moved into the vessel beneath thecontainer, until the far end of the container is engaged and the drivemotor then reversed to pull the containers from the vessel and onto therails of the unloading apparatus. The transfer chains of the unloaderthen move the containers along the rails and onto the unload shuttleconveyor 40. From the unload shuttle conveyor, the now washed and/orsterilized containers are transferred onto a conveyor 41 for routing toa point of use.

While the invention has been described as if the loading and unloadingconveyors 20 and 40 respectively moved the containers along a path oftravel normal to the path through the vessel's, it is considered withinthe skill of the art to have these conveyors disposed in line with thedirection of loading. In this respect for example, load conveyor 20could be disposed to feed containers in line towards the vessel openingto a point where the containers can be picked-up by dog 66 on theendless chain and moved into the vessel as described hereinabove.

Thus, it should be appreciated that the present invention accomplishesits intended objects in providing a loading apparatus, particularly forwashers, sterilizers and like vessels in which no movable part of theapparatus remains within the vessel and which may transfer articles froma conveyor mechanism and into the vessel.

Having thus described the invention, what is claimed as new is:

1. Apparatus for loading articles into washers, sterilizers and the likevessels comprising in combination:

a. a guide and support track located in front of and spaced from anopening of the vessel for receiving an article to be loaded;

b. an endless chain supported for movement in a closed loop, a portionof which loop extends along a path of travel beneath said track, one endof said loop being defined by a sprocket in front of and spaced fromsaid vessel opening so as to define a space between said loop end andvessel opening;

a dog on said chain extending upwardly and engageable against a bottomportion of an article on said track;

d. first drive means driving said chain about said loop in one directiononly for engaging said dog against the article and moving the articlealong said track and across said space to a first position partiallythrough said vessel opening, said dog thereafter disengaging from thearticle at said loop end, as said chain passes over said sprocket;

. a moveable cantilevered boom supported in a rest position outside ofsaid vessel and beneath said track for reversable movement into and outof the vessel opening, a portion of said boom extending upwardly andengageable against a bottom portion of an article on said track;

. reversable means for driving said boom to engage ond means isactivated while said first means is operating and before the article ismoved across said space, said second means being adapted to drive saidboom at a speed slower than said first means drives said chain wherebysaid boom engages the article after disengagement of said dog.

1. Apparatus for loading articles into washers, sterilizers and the likevessels comprising in combination: a. a guide and support track locatedin front of and spaced from an opening of the vessel for receiving anarticle to be loaded; b. an endless chain supported for movement in aclosed loop, a portion of which loop extends along a path of travelbeneath said track, one end of said loop being defined by a sprocket infront of and spaced from said vessel opening so as to define a spacebetween said loop end and vessel opening; c. a dog on said chainextending upwardly and engageable against a bottom portion of an articleon said track; d. first drive means driving said chain about said loopin one direction only for engaging said dog against the article andmoving the article along said track and across said space to a firstposition partially through said vessel opening, said dog thereafterdisengaging from the article at said loop end, as said chain passes oversaid sprocket; e. a moveable cantilevered boom supported in a restposition outside of said vessel and beneath said track for reversablemovement into and out of the vessel opening, a portion of said boomextending upwardly and engageable against a bottom portion of an articleon said track; f. reversable means for driving said boom to engage saidboom portion against and move the article from said first positionthrough said opening and into said vessel, said reversable meansthereafter operating to move said boom out of said vessel; and g. switchmeans engagable by the article for deactuating said first drive meansand actuating said reversable drive means when the article is at saidfirst position.
 2. Apparatus as set forth in claim 1 in which saidsecond means is activated while said first means is operating and beforethe article is moved across said space, said second means being adaptedto drive said boom at a speed slower than said first means drives saidchain whereby said boom engages the article after disengagement of saiddog.